Jet boat propulsion unit



z2., 1%? j M s; SMITH www2 JET BOAT POFULSION UNIT Filed July 16, 1965 ug. 22, g? M s, SMlTH JET BOAT PROPULSION vUNIT 3 Sheets-$heet 2 Filed July 16, 1955 M. S. SNHTH JET BOAT. PROIPULSlON UNIT ug 22, E67

5 Sheets-Sheet 3 sisi...

Filed July 1G, N55

United States Patent O 3,336,752 JET BOAT PROPULSION UNIT Morley S. Smith, Indianapolis, Ind., assignor to The Buehler Corporation, Indianapolis, Ind., a corporation of Indiana Filed July 16, 1965, Ser. No. 472,495 4 Claims. (Cl. 60-221) The present invention relates to a propulsion system for `a water jet propelled boat.

There are presently available a number of different types of jet propelled boat arrangements. One such arrangement includes an engine and 4a pump both mounted inboard of the boat with a controlling gate or valve mounted outside of the boat Ion the tail pipe of the pump. Various problems are present in the construction and operation of this type system. For example, some means must be provided for steering the boat while moving in reverse. Furthermore, the pump and engine occupy substantial space inside the boat which cannot, therefore, be occupied by passengers and other load.

Another propulsion system for jet boat might involve a structure similar to an outboard motor. Such a mechanism is disclosed, for example, in the patent to K. H. Bergin 3,046,735. Obviously the engine of the motor in the latter type of arrangement cannot be very heavy or else the mechanism cannot be mounted on the relatively weak transom of a conventional small boat. Also, the latter type of arrangement is not particularly adapted for use where the engine is relatively large and heavy because the boat is rendered top heavy and, therefore, easy to capsize.

One object of the present invention s to provide animproved jet boat propulsion system.

A further object of the present invention is to provide a jet boat propulsion system which incorporates the advantages of the above mentioned propulsion systems but eliminates the disadvantages thereof.

A further object of the present invention is to provide a jet boat propulsion system which can be easily steered while moving both forwardly and in reverse.

Still another object of the present invention is to provide a jet boat propulsion system incorporating means for reducing spray.

A further object of the present invention is to provide a jet boat propulsion system which is swingable upwardly to avoid obstacles yet which is yoperable to propel the boat while moving backwardly.

Still a further object of the invention is to provide an inlet to -a water jet pump which is more efficient than known configurations.

Related objects and advantages will become apparent as the description proceeds.

One embodiment of the present invention might include a -pump housing, a pump contained within said pump housing, a support element mounted on the transom of said boat for pivoting about a generally vertical axis, said pump housing being mounted on the support element for pivoting about a horizontal axis but engageable with an abutment portion of said support element to block downward pivoting below a position wherein said housing projects generally rearwardly of said boat, an engine mounted on said boat and having a drive shaft, universal joint means coupling said drive shaft and said pump whereby said pump housing can be pivoted on said support element to steer said boat while said engine simultaneously drives said pump.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims.

.FIG. 1 is a side elevation of a jet boat incorporating the present invention.

3,336,752 Patented Aug. 22, 1967 FIG. 2 is an enlarged side elevation similar to FIG. 1 but with portions broken away and portions in section.

FIG. 3 is primarily a longitudinal vertical section taken through the rearward portion of the structure of FIG. l and generally along the axis of the jet boat pump.

FIG. 4 is a generally vertical section taken along the line 4-4 of FIG. 2 in the direction of the arrows.

FIG. 5 is an enlarged section taken along the lines 5-5 of FIG. 2 in the direction of the arrows.

FIG. 6 is a View Vgenerally similar to FIG. 2 but showing the clam shell gate of the present invention in a different operating position.

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modilications in the illustrated device and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

Referring more particularly to the drawings, there is illustrated a boat 10 having an engine 11 mounted therein. The engine 11 incorporates internally splined output means 12 which slidably receives externally splined shaft 15. In one embodiment of the present invention the eX- ternally splined shaft 15 is fixed directly to the engine. In the illustrated embodiment, however, the slidable connection between'the member 12 and the shaft 15 facilitates mounting of the engine in the boat 10 and reduces transmission of vibration from the engine to the transom 16.

An internally splined sleeve -17 is fixed against longitudinal movement relative to the shaft 15 by means of a pin 20. The sleeve 17 rotates within bearings 21 which are spaced apart by annular sleeves 22. The bearings 21 are retained in position by snap rings 25 which respectively engage sleeve 17 and a bearing housing 26 iixed by bolts 27 to a gimbal ring support element 30. The support element 30 is fixed by suitable bolts '31 to the transom 16.

A conventional automotive type universal joint 35 is coupled by its internally splined sleeve portion 36 to the externally splined shaft 15. The internally splined portion 36 is axially slidable relative to the shaft 15 in order to permit the pump housing 37 to be swung rightwardly or leftwardly for steering the boat. The universal joint 35 (which incorporates the usual four trunnion element 34 connecting universal joint members 36 and 33) may have its hollow internal portion 40 packed with oil or grease at the factory whereby the universal joint is lubricated for the life thereof.

Fixed to the support element 30 is a rearwardly extending annular liange 41 upon which is received one end 42 of a bellows. The one end 42 is clamped to the ange 41 by a suitable ring clamp 46. The other end 47 of the bellows is received about an annular liange 50 integral with a bearing capsule cap 51. It can be appreciated that the bellows 45 protects the universal joint contained therewithin against corrosion and protects the universal joint from throwing a spray of oil or water while the present device is in operation. Because of the accordion nature of the bellows, it can flex with the pump housing 37 as it is swung horizontally for steering.

The pump housing 37 is mounted upon the boat by means of a bearing Acapsule 52 which is fixed to the pump housing and is pivoted about the horizontal axis 55 to a gimbal ring 56 by a pair of pivot pins 54 one of which secured in position by a set screw 53 and rotates in a bearing 57 mounted in the bearing capsule 52. The gimbal ring 56 is pivotally secured to the support element 30 by means of generally vertically extending trunnion elements 60 and 61 which are pinned to the gimbal ring by members 62 and which rotate in bearings 65 mounted in the support element 30. The upper end of the trunnion element 60 has pinned thereto a steering lever 66, said steering lever extending through the transom of the boat.

It will be noted from FIG. 3 that the bottom 70 of the boat when extended or projected, intersects a substantial portion of the pump housing whereby a substantial portion of the pump housing is located lower than the boat bottom and beneath the surface f the water within which the boat is floating or supported. This relationship is i1- lustrated in FIG. 1 wherein the surface of the water is indicated at 79 and a portion 71 of the pump housing projects beneath the surface 79 of the water. The pump housing 37 has a lip 72 which projects downwardly beneath the surface of the water a substantial distance so that las the boat is moving forwardly through the water the surface water is deflected sidewardly and the inlet opening 75 in .the bottom portion of the pump housing takes in its intake water from suflicient depth so that the inlet water has not been given a forwardly moving component of energy by the bottom of the boat.

The pump housing 37 has formed integrally thereon oppositely projecting cavitati-on plates 76 which :are located just above the surface 70 of the water and which function to reduce spray caused by the portion 71 of the pump housing moving through the water. Preferably the pump housing 37 is generally formed in two portions including the intake portion 77 and the tail pipe portion 80. Of course, each of the portions 77 and 80 has an integral cavitation plate 76.

The bearing capsule 52-has received therein a bearing 80. There is received on both sides of the bearing 80 oil seals 81 which function to retain the lubricating oil within the bearing 80. The further seal 82 is received within the recess 85 in the pump housing and functions to prevent water from flowing from the inside -of the pu-mp housing between the shaft 86 and the pump housing into the recess 85. A sleeve 90 is pinned to the shaft 86 by the pin 91 and functions to mount the various seals 81 and 82 and the bearing 80. The shaft 86 is coupled to the universal joint member 33 by a suitable key 87 and by a washer 98 retained on the end of the shaft 86 by nut 99. The shaft 86 drives a single impeller 92 which is secured to the shaft 86 by the key 95. The rearward end 96 of the shaft is supported in a metal bearing 97 secured in position by the washer 100 and bolt 101. The metal bearing 97 is mounted within a grooved rubber bearing 98. The bearing 98 is mounted within a cup shaped element 102 which is open at its forward portion 103 :and also has a central opening 105 at its rearward end. Thus water can ilow between the single impeller '92 and the member 102 past the rubber bearing 98 and out the opening 105 in the rear of the lcup element 102 for lubricating the bearing. The cup shaped member 102 is mounted on the pump housing by radially extending straightening vanes 106.

At the inlet 75 of the pump housing 37 there is provided longitudinally extending strainer including grill members 110 (see FIG. 4). The members 110 have substantial depth as compared to their horizontal width so that the members 110 provide a steering action whether the boat is moving forwardly or rearwardly. This steering action is effected on water moving into the inlet opening 75 as well as water moving past the inlet opening. The grill members 110 are bolted to the pump housing by bolts 111 at the forward and rearward ends thereof.

A clam shell gate 120 is swingably mounted on the pump housing 37 by means of pins 121 and is movable from the upward position illustrated in FIG. 2 and FIG. 4 to the downward position illustrated in FIG. 6. The gate 120 incorporates internal support members 122 which also function to support the clam shell gate against the rearward end of the tail pipe 71 of the pump housing. It can be appreciated from an examination of FIG. 6 that the water leaving the nozzle 126 mounted in the tail pipe will -move into the hollow interior 127 of the gate and will be deflected downwardly beneath the pump housing 37 so as to give the boat a rearward thrust. When the boat is moving in reverse in this manner, it can be steered by means of the steering lever 66. As the boat moves rearwardly through the water, the grill members 110 function to guide the water being deflected by the gate and also to guide the boat by engaging the water within which the boat is flowing or is supported.

Referring to FIGS. 3 and 5, there is fixed to the gimbal ring 56 a pair of rearwardly extending projections 150, each of which has three holes 151 therethrough. Depending upon the angle at which it is desired the pump housing project from the rear of the boat, a rod 152 is mounted through a selected one of holes 151 in the rearwardly extending projections 150. The pump housing 37 has a pair of integral forwardly extending projections 155 on its forward upper surface, said projections 155 being adapted to engage the rod 152 so as to prevent the pump assembly 37 from swinging downwardly past the position illustrated in FIG. 3. Of course, the downward position of the pump housing is lower or higher than the position of FIG. 3 if the rod 152 is mounted in upper holes or lower holes 151, respectively. It can be appreciated that when the boat is moving forwardly through the water, the portion 71 of the pump assembly which projects substantially beneath the bottom of the boat may strike an obstruction. The pump assembly, however, is free to swing upwardly about the axis 55 of the pins 54 to avoid such obstruction.

When the boat is moving in reverse, however, it is desired that the pump assembly 37 be locked in its illustrated downward position as shown in FIG. 6 so that full rearward thrust can be achieved in the proper direction. The mechanism illustrated in FIGS. 2 and 5 makes possible the locking of the pump housing in the downward position. This mechanism includes a pair of hooks 161, one on each side of the pump housing. The hooks are pivotally secured to the housing by respective bolts 162 which project into the respective abutment members 155. Each hook 161 is pivoted upwardly to engage the rod 152 by means of a respective link 165 pivotally secured at its opposite ends to the hook 161 and the clam shell gate 120. The gate 120 is moved between its downward position of FIG. 6 and its upward position of FIG. 2 by means of a flexible rod or wire contained within a flexible housing which is fixed by a bracket 171 to the top of the pump assembly. The flexible cord or wire is secured at its rearward end to one end of a lever 172, pivoted by bolt 173 to the pump assembly and pivotally secured at its other end by link 175 to the clam shell gate 120.

From the above description it will be evident that the present invention incorporates an improved jet propulsion system which incorporates the advantages of both the inboard and outboard mounted jet boat propulsion system and eliminates the disadvantages thereof. It will also be evident that the present invention provides a jet boat propulsion system incorporating improved means for reducing spray. It will also be appreciated that the jet propulsion system of the present invention is so constructed that the entire jet pump is external to the boat and the driving engine is located inside the boat with the shaft of the jet pump in line with the shaft of the engine and therefore requiring no gears, belts or chains to transmit power from the engine to the pump.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that al1 changes and modications that come within the spirit of the invention and the scope of the claims are also desired to be protected.

The invention claimed is:

1. In a jet boat, a pump housing, a pump contained within said pump housing, a support element mounted on the transom of said boat for pivoting about a generally vertical axis, said pump housing being mounted on the support element for pivoting about a horizontal axis but engageable with an abutment portion of said support element to block downward pivoting below a position wherein said housing projects generally rearwardly of said boat, an engine mounted on said boat and having a drive shaft, universal joint means coupling said drive shaft and said pump whereby said pump housing can be pivoted on said support element to steer said boat while said engine simultaneously drives said pump, said pump housing having an inlet at a lower portion thereof and an outlet at a rearward portion thereof, a clam shell type reversing gate swingably mounted on said pump housing for movement between a rst position above the pump housing wherein the rearward portion of said pump housing is unobstructed and a second position to the rear of said pump housing whereby the jet stream is deflected beneath the boat, a hook pivotably mounted on said pump housing, said hook being linked to said reversing gate and swingable, by the moving of said gate to said second position, into a position beneath and engaging said support element and locking said pump housing against upward pivoting movement.

2. The arrangement of claim 1 wherein said abutment portion of said support element is removable and remountable on said support element to vary the generally rearwardly projecting position of said pump housing.

3. In a jet boat, a pump housing, a pump contained Within said pump housing, a support element mounted on the transom of said boat for pivoting about a generally vertical axis, said pump housing being mounted on the support element for pivoting about a horizontal axis but engageable with an abutment portion of said support element to block downward lpivoting below a position wherein said housing projects generally rearwardly of said boat, reversing means aixed to said housing and being operable between a iirst position wherein the jet stream is unaiected and a second position wherein the jet stream is deflected beneath the boat, and locking means linked to said reversing -means and movable, by the moving of said reversing means to said second position, into a position locking said pump housing to said support element and against upward pivoting movement.

4. The arrangement of claim 3 wherein said abutment portion of said support element is removable and remountable on said support element to vary the generally rearwardly projecting position of said pump housing.

References Cited UNITED STATES PATENTS 2,860,594 11/1958 Kiekhaefer 115-17 3,105,353 10/1963 Schulz 115-12 X 3,212,258 10/1965 Gongwer 11S-16 FOREIGN PATENTS 1,335,579 7/ 1963 France.

3,207,116 9/ 1965 France.

MILTON BUCHLER, Primary Examiner. T. M. BLIX, Assistant Examiner. 

3. IN A JET BOAT, A PUMP HOUSING, A PUMP CONTAINED WITHIN SAID PUMP HOUSING, A SUPPORT ELEMENT MOUNTED ON THE TRANSOM OF SAID BOAT FOR PIVOTING ABOUT A GENERALLY VERTICAL AXIS, SAID PUMP HOUSING BEING MOUNTED ON THE SUPPORT ELEMENT FOR PIVOTING ABOUT A HORIZONTAL AXIS BUT ENGAGEABLE WITH AN ABUTMENT PORTION OF SAID SUPPORT ELEMENT TO BLOCK DOWNWARD PIVOTING BELOW A POSITION WHEREIN SAID HOUSING PROJECTS GENERALLY REARWARDLY OF SAID BOAT, REVERSING MEANS AFFIXED TO SAID HOUSING AND BEING OPERABLE BETWEEN A FIRST POSITION WHEREIN THE JET STREAM IS UNAFFECTED AND A SECOND POSITION WHEREIN THE JET STREAM IS DEFLECTED BENEATH THE BOAT, AND LOCKING MEANS LINKED TO SAID REVERSING MEANS AND MOVABLE, BY THE MOVING OF SAID REVERSING MEANS TO SAID SECOND POSITION, INTO A POSITION LOCKING SAID PUMP HOUSING TO SAID SUPPORT ELEMENT AND AGAINST UPWARD PIVOTING MOVEMENT. 